Modification of ethylmethane sulfonate-induced mytagenesis with adrenaline

Experiments withCrepis capillaris dry seeds show that pretreatment with adrenaline hydrochloride and adrenaline hydrotartrate significantly reduces the number of aberrations induced by the supermutagen ethylmethane sulfonate. The effective concentration ranges for adrenaline adrenaline hydrotartrate and hydrochloride are 10⁻¹–10⁻⁷ M and 10⁻³–10⁻⁷ M, respectively. Adrenaline hydrochloride is more effective than adrenaline hydrotartrate (79.1vs. 65%, respectively). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 10, pp. 427–429, October, 1998     

Mechanism of arterial pressure elevation in calcium deficiency

We compared the effects of intravenous administration of the calcium-dependent hypertensive factor from the plasma of patients with essential hypertension and of a synthetic heptapeptide with hypertensive activity. Both substances prove to induce prolonged and pronounced elevation of arterial blood pressure. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 476–477, May, 1994 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences     

Potentiating effect of thyrotropin-releasing hormone and of its synthetic analog digipramine on morphine-induced analgesia

Thyrotropin-releasing hormone (TRH) and its synthetic analog digipramine (DP) shortened the latency of the tail-flick response in mice when injected intraperitoneally in a dose of 5 mg/kg and to potentiate significantly the analgesic action of morphine. Possible mechanisms of these two effects and prospects for their medical use are discussed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 117–119, August, 1994     

Early stages in the mechanism of action of glucocorticoids on human platelets. Effect of hydrocortisone on intracellular cAMP and Ca2+ content

Changes in basal and stimulated levels of cAMP and calcium induced by hydrocortisone in a wide range of concentration (0.1–25 μM) are studies in a suspension of washed human platelets. The effects of hydrocortisone on the activity of preparations modulating various stages of the adenylate cyclase system (forskolin, adenosine, adrenaline, and 3-isobutyl-1-methylxanthine) are compared. Platelets are stimulated with collagen, platelet activating factor, and thapsigargin. Hydrocortisone in different concentrations acts as both activator and inhibitor of calcium metabolism in platelets. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 6, pp. 663–665, June, 1997     

Vestibuloprotective and antiamnestic properties of adrenocorticotropic hormone fragments and their analogs

It is established that low-intensity electromagnetic waves of superhigh frequency and motion sickness induce in rats a retrograde amnesia revealed in the passive avoidance test. Fragments of adrenocorticotropic hormone (ACTH) (4–10) and (5–10), ORG-2766 [ACTH (4–9) analog], and a domestic ACTH (4–10) analog, ACTH (4–7)-Pro-Gly-Pro (semax), in doses of 0.05–0.1 mg/kg significantly weaken the anamnestic effect of both extreme factors. Semax and ORG-2766 also possess a marked anti-motion sickness activity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, Nulo 6, pp. 634–636, June, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

An appropriate increase in the proportion of blood flow through the superior vena cava to the total venous return during systemic cardiovascular responses

Systemic pressor and depressor reactions induced by catecholamines, angiotensin II, adrenoblockers, antianginal preparations (corinfar, mesotrin, nitroglycerin), hypoxic hypoxia, and hypothermia in normo-and hypertensive animals are accompanied by an appropriate decrease in the proportion of blood flow through the superior vena cava and an increase in that through the inferior vena cava in the total venous return. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 4, pp. 376–380, April, 1996 Presented by B. I. Tkachenko, Member of the Russian Academy of Medical Sciences     

Effect of μ-opiate receptor agonist tetrapeptide A10 on DNA synthesis and protein content in the myocardium of albino rats

Effect of intraperitoneal injection of tetrapeptide A10 (H-Tyr-D-Orn-Phe-Gly-OH), selective μ-opiate receptor agonist, synthetic analog of dermorphine, in a dose of 100 μg/kg on DNA synthesis and protein content in the myocardium was studied in albino rats. Five injections of tetrapeptide on days 2–6 after birth caused no changes in DNA synthesis 17 days after the last injection,i. e. in 24-day rats. The number of nucleoli and their area increased. In adult males long-term (3-week) treatment with tetrapeptide A10 increased the number of nucleoli and the mean and integral optical density of isolated cardiomyocytes stained with amido black B, which probably attested to activation of protein synthesis in the myocardium. Simultaneously, the content of catecholamines in the heart increased. These data are comparable with delayed effects of κ-opiate receptor agonist dinorphine A_1–13 and indicate that morphogenetic properties of opioid peptides in rat myocardium are realized via the same routes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 12, pp. 693–695, December, 2000     

Serological assessment of synthetic peptides of <Emphasis Type="Italic">Campylobacter jejuni</Emphasis> NCTC11168 FlaA protein using antibodies against multiple serotypes

The flagellum of Campylobacter jejuni is not only responsible for initiating colonization of the gastrointestinal tract of host animals but is also a major antigen that induces protective immune responses. However, protection is limited to the homologous strain and the ability to protect against multiple serotypes has yet to be determined. In this study, we have shown that FlaA is an immmunodominant protein on NCTC11168 CJ1 flagella and we mapped the immunoreactive epitopes on the protein by probing a series of overlapping synthetic peptides spanning the entire sequence with sera against multiple C. jejuni serotypes. Amino acid residues 176–205 (P8), 376–405 (P16) and 501–530 (P21) were immunodominant and cross-reactive. The mucosal IgA in the intestinal secretions of CJ1-infected birds reacted significantly with peptides P16 and P21 indicating that the specificity of the mucosal response is different from the systemic response. Antisera raised against formalin-killed CJ1 cells and purified flagellin showed positive reactivity with a subset of peptides identified by antisera against live C. jejuni. This study provides insight into the specificity of the host immune responses to the FlaA protein of C. jejuni and suggests that these sequences merit further testing for their immunogenicity and potential as subunit vaccine candidates for multiple serotypes.     

Neurotropic effects of a luliberin analog administered intraventricularly to rats with different sensitivities to ethanol

In experiments with random-bred male rats separated into short and long sleepers according to the duration of ethanol-induced sleep (narcosis), a synthetic luliberin analog (Surfagon) administered into a brain ventricle was found to reduce pain sensitivity and affective aggressiveness in response to unavoidable painful electrostimulation, and to increase convulsive activity. Short-sleeping rats differed from long-sleeping ones in showing greater behavioral excitability and aggressiveness and in being more responsive to Surfagon, which lowered both these parameters in the former rats to a greater extent than in the latter before castration as well as after it. Mechanisms of the observed behavioral effects of Surfagon are discussed, and it is concluded that they are not mediated by sex steroids, and that the major factor in the mechanisms of its action is the accessibility of limbic structures and of the central gray substance in the midbrain. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No. 2, pp. 129–132, February, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Amine-containing lymph node structures during chronic glucocorticoid administration

Luminescent histological studies show that synthetic corticosteroid triamcinolone acetate induces a bioamine reaction in intrafollicular and paracortical macrophages in lymph node. Long-term administration reduces the number and size of lymph node follicles (B-zone) and paracortical cells. Chronic (1 month) administration of hydrocortisone elevates the content of serotonin and catecholamines in the B-dependent zone and serotonin content in paracortical macrophages. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 3, pp. 270–272, March, 1999     

Temporal variations in hemodynamic effects of immobilization stress in normotensive,stress-susceptible,and spontaneously hypertensive rats

Using the catheter technique, temporal variations in arterial pressure and heart rate were examined before, during, and after a 60-minute immobilization-induced stress in normotensive, spontaneously hypertensive, and stress-susceptible awake rats. Stress-susceptible rats developed a hypertensive response to the stress more rapidly than did either normotensive or spontaneously hypertensive animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 11, pp. 478–480, November, 1995     

Effect of boron on the ultrastructure of parathyrocytes and atrial cardiomyocytes

Ultrastructural shifts in parathyrocytes and atrial cardiomyocytes induced by long-term treatment with boron-containing water (250 mg/liter) were found against the background of boron accumulation. These changes are indicative of enhanced secretory activity of these cells. It is hypothesized that boron modulates the effect of parathyroid hormone and atrial natriuretic factor and the rate calcium-sodium exchange. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 111–114, July, 1997     

Direct antiatherogenic effect of garlic

Blood serum of patients with documented coronary atherosclerosis induces intracellular cholesterol accumulation in a primary culture of human aortic intimal cells. Serum prepared from blood collected 2–4 h after administration of a tablet containing 300 mg garlic powder (Kwai, Germany) induces a much lower cholesterol accumulation in cultured cells. A tablet with the same amount of garlic but with a prolonged effect (Allikor, Russia) lowers serum atherogenicity for 12–14 h. The direct antiatherogenic effect of garlic powder is confirmed by cell culture experiments with aqueous extracts from garlic powder. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 6, pp. 695–697, June, 1996     

Potentiating and delayed effects of dalargin analogs on the duration of nembutal-induced sleep

Simultaneous administration of Nembutal and the dalargin analog No. 3 prolongs duration of sleep in all rats and in 17% of mice by 25–450%. Administration of the dalargin analog No. 3 twenty-four hours before Nembutal results in a 2- to 3-fold increase in the duration of sleep compared with that after simultaneous administration of Nembutal and the analog. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 12, pp. 618–622, December, 1996     

Effect of tumor necrosis factor-α on thein vitro synthesis of interleukin-8 by human monocytes and lymphocytes

The addition of recombinant tumor necrosis factor or monoclonal antibodies to this factor into human monocyte culture does not change the synthesis of interleukin-8. By contrast, tumor necrosis factor induces the synthesis of interleukin-8 in human lymphocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 8, pp. 200–202, August, 1996     

Interrelationship between the membrane potential of adrenocorticocytes and functional activity of the adrenal glands in adult and old rats

Experiments on adult (5–7 months old) and old (28–30 months old) male rats reveal that ACTH induces a hyperpolarization of the plasma membrane of adrenocorticocytes from the fasciculate zone in both age groups of animals 24 hours after a single administration of the hormone. Actinomycin D, an inhibitor of protein synthesis, prevents the development of hyperpolarization. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, № 3, pp. 302–303, March, 1994 Presented by D. F. Chebotarev, Member of the Russian Academy of Medical Sciences.     

Synthetic peptide, a fragment of the β-subunit of chorionic gonadotropin, inhibits mitogen-stimulated proliferation of human lymphocytesin vitro

Similar to chorionic gonadotropin, synthetic fragment of the β-subunit of chorionic gonadotropin (128th–145th amino acid), inhibits mitogen-stimulated proliferation of human lymphocytesin vitro and binds to membrane receptors of human peripheral blood monocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 319–322, March, 1997     

Effect of pollack liver oil in rat testes

Rat testes are studied 1, 3, 6, and 12 month after addition of pollack liver oil (0.1 g/kg body weight) to daily ration. A 3-month feeding of the fish-oil-enriched diet leads to degenerative changes of spermatozoa and spermatids in 8–12% convoluted tubules. Continuation of the treatment to 6–12 months induces damage to spermatocytes and spermatogonia in 30–60% tubules. The observed changes can be attributed to consumption of high doses of retinol, a constituent of pollack liver oil. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 340–343, March, 1997     

Effect of adrenaline on hypothalamic neurohormone stimulation of the functional activity of the sterlet interrenal glandIn vitro

In vitro experiments on sterlet kidney fragments with interrenal glands showed that vasotocin and oxytocin activated the function of these glands, while simultaneous exposure to these neurohormones and adrenaline virtually did not modify the functional activity of the glands. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 7, pp. 54–55, July, 1999     

Effect of melittin on the contractility of rat papillary muscle

Melittin, a phospholipase A₂ activator, induces two-phase changes in the contractility of isolated rat papillary muscle. The first phase is characterized by an increase in the force of muscle contraction during the first 5–15 min of perfusion, the increase being the greatest at 0.4 μg/ml melittin. This phase is abolished by 10 μM indomethacin. In the second phase, dose-dependent inhibition of muscle contraction reaches the maximum after 30–45 min of perfusion and is abolished by the lipoxygenase inhibitor nordihydroguaiaretic acid (10 μM). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 25–27, July, 1997